Grid bar for fiber-treating machines



M. WEHLI GRID BAR FOR FIBER TREATING MACHINES Fil9d A112. 18. 1926IMF/7M: //0 M1 3 M 1 11 5/ JIM/IE) Patented Mar. 6,1928.

UNITED STATES MORRIS WEHLI, OF BASED, SWITZERLAND.

GRID BAR FOR FIBER-TREATING MACHINES.

Application filed August 18, 1926, Serial No. 130,060, and in FranceJanuary 28, 1926.

This invention relates to bars for the grids of machines for opening,clean1ng,'beatmg,

carding or parallelizing cotton waste and other kinds of fibers.

The object of the invention is to provide an improved construction ofgrid bar whereby the removal of waste or impurities from the fibers isfacilitated and the presence of dead spaces or eddying spaces betweenthe bars is obviated, so that impurities or fibers are prevented fromadhering to the sides of the bars.

With this end in view, the present invention consists in the provisionof grid bars which are constructed with a stream-line surface, in orderto allow the incoming streams of air to pass through the spaces betweenthem without eddying and without the occurrence of dead spaces, in sucha manner that between the entry of the air streams into the grid orgrating'and their exit therefrom, a reduction in velocity and a drop npressure take place due to the increase in cross-section of the spacesbetween the respective bars.

Reference will now be made to the accompanying drawings, in which Figure1 represents, as an example, a vertical cross-sectional view of a gridfor a card breaker of known type made up of such bars; and Fig. 2 is adetail view,.partly in sectional pen spective, showing the mounting of abar.

As will be apparent, the said grid presents the peculiarity of beingconstituted by bars A comprising at their upper part a rim or flange Band, below said flange, over the whole or a part of their length aninwardlycurved recess C, the section of which may advantageously (butnot necessarily) have the shape represented in Fig. 1; suchrecess beingformed in the inside portion of the bar between the flange or rim B andthe bottom edge of the bar. Any suitable means may be employed forsupporting the bars.

The aforesaid recess C is arranged transversely to the current of air,and it gives to the bars a stream-like form, so that the air streamssweep entirely over the whole of the grid bars and thus prevent dead oreddying spaces being formed, and also prevent any impurities romadhering to the bars. The increase in the cross-sectionof the grid spaceor opening effects a change in velocity of the air and also a drop inpressure between the entry and exit of the air into and from the grid,this action freeing the fibers from their impurities which fall throughthe grid.

The purpose of the present invention is to imprison air, retarding itsentry into the grid, in order that the impurities which are heavier thanthe fibers will be more eiiicientl y separated and fall under thegrid,while the fibers will remain on the grid and be carried further on.Owing to the operation of the licker-in or of the beater,'the air drawnin is throttled in recesses C so that a forcing back of air takes place,producing a dead point and helping to expel the impurities. Barsconstructed as above will also prevent cotton as well as impurities orother matter from sticking on the ends of the bars, so that any shortfibers and impurities that might happen to gather will drop throughtheir own weight instead of adhering to the bars or being drawn into themechanism of the machine, as is the case with hitherto-known grids.

I claim as my invention:

1. A grid for scutchers, beaters, carding machines and the like,embodying grid bars which, in order to allow the incoming streams of airto pass through the spaces be tween the bars without eddying and Withoutthe occurrence of deadspaces, have their inside portions, between thetop and bottom edges thereof, constructed with a stream-line surfaceproducing an increase in the crosssectional area of said -grid spaces,so that between the entry of the streams into the grid and their exittherefrom a reduction in velocity and a dro in ressure take place.

2. A grid according to claim 1, in which the inside portions of the gridbars are hollowed out to form the stream-line surface, so that the pointof greatest depth of such surface corresponds to the point of largestcross-section of the space between two consecutive bars and of minimumair speed, and the streams of air entering into the grid flow throughthe latter without forming dead or eddying spaces.

In testimony whereof I aflix my signature.

MORRIS WEHLI.

